Brake control valve mechanism



Oct.'14, 1941. T. A. s'rEHLlN BRAKE CONTROL VALVE MEGHANISM Filed Oct. 5, 1959 Snventor 7,4; 57E/HLW.

BH www Cttomeg Oct. 14,y 1941. "Ir, A. sTEl-ILIN 2,259,134

BRAKE CONTROL VALVE MECHANISM Filed Oct. 5, 1939 2 Sheets-Sheet 2 11; ffl/1 /J") fj/fd Tja 4 Ff a. i

:inventor TASTE/aw.

Gttorncg Patented Oct. 14, 1941 Hawaiiy Application October 5., 1939, Serial No. 298,080'

(Cl. 3D3-"54) 14A Claims.'

rllhis invent-ion relates to brake mechanisms,

and more particularly to a brake control valve mechanism therefor. Thisapplication is a ccntinuation' in part of application Serial No. 104,071, for Vehicle wheel brake control, led October v5, 1936, now Patent No. 2,200,659 dated May 14, 1940.

One of the principal objects of this invention ever, upon the speed of depression or manipulation of a manually controlled lever o'r pedal.

A further important objectv o'f this invention is the' provision of means in connection withsuch brake control valve mechanism in which the loss of fluid pressure is' reduced to a Aminimun-i when the brake mechanism is notl in operati-on, that is', in which the fluid under pressure is shutV oft or sealed when the brakes are not applied An important object of this inventionI also is the provision of a brake' controlling means which is particularly simple and economical of com struction, operation and installation, and which will not readily deteriorate or get out'of order.

With these and other objects in View as will appear hereinafter, I have devised a brake valve control mechanism o'f this class having certain novel features of construction, combination, and

had te the aeeergipanying drawings and to' theV characters of reference thereon, wliioh form a Fig. e is a diagrammatic view snowing the op- 2 erating plunger of lthe control valve partly depressed or forced into the valve; and,

lig.` 5 is a similar diagrammatic view thereof showing the plunger wholly depressed.

I shall describe my fluid brake control Valve mechanism in conneotio'n with or as may be particularlyusedon automobiles, trucks, streetcars, trains, or thelike. I

The controlI valve itself o-f my mechanism consists essentially of a cylindrical casing I in which is reciprocally mounted a double or opposed `pistori` .2, a plunger 3 coaxially and reciprooally mounted With respect tothe casing and the piston, and springs and 5 in association respectively with the piston and the plunger for urg-l ing both in the same direction toward one end of the casing. The easingis cylindrical and preferably positioned vertically with the upper end provided with a fitting I I connected to the brakes Which are to be applied, and provided` intermediate its ends with a itti'ngA If connected to the desired vacuum sources. Thecasing is also provided with' pipe connections I3 and Irl intermediate its ends, Iwhich pipe extends to pressurev gages (not shown)` preferably located on the instrument boa-rd of the vehicle, for indicating to the driver respectively the-fluidpressure or the vacuurn in the portion of thecasing connection to the vacuum sources", and the pressure of the fluid which is to actuate the brakes. ,y

p l e piston 2V is in the form of a spool havingv cup leathers 25 at its opposite ends, forming an annular channel 2` intermediate its ends, which annula channel' is at all times connected to the pipes or fittings I2 and I3, or to the vacuum sources and the gage, except as hereinafter described. The piston is urged toward the lower end of thecylindrical casing by the compression springtn 4,- The plunger 3 is provided with a shoulder 3a intermediate its end, which shoulder is forced against the lower end of the cylindricalr casing, as a stop, by the compression spring 5 positioned outside of the cas-ing between the casving and the lower end of the plunger. The upper endof the plunger-has a central boreb, the lipperend of which communicates at all times with the upper end of the casing, and therefore with the pipe or fitting I I leading to the brakes.

The bore of thel piston, through which the plunger extends, is undercut intermediate its ends, forming an annular chamber 2c which communicates through laport 2d, with the large annular channel 2b. This port 2 d is preferably locatednear'er the upper end of the annular channe1 2b than the lower end. in the wail of the -positioned immediately below the lower end ofL lower end of the annular chamber 2C which is connected at all times with the source of the vacuum. A partial vacuum is immediately created in the brake line, which includes the upper portion Ic of the casing I. Such partial vacuum immediately acts upon the piston 2 and tends to draw the piston upwardly against the compression of the spring 4, and tends to close the port 3. If the plunger is raised no further, the action upon the brakes and the raising of the piston 2 is equalized. Consequently there is only slight the spool or piston. The lower end of the casing I is also provided with a port Ia which, whenv the plunger is in its lowerrnost orinoperative position, connects the atmosphere, through the plunger and the pipe or fitting I I with the brakes and thus neutralizes any action upon the brakes.

The tension of the piston actuating spring 4 may be adjusted to vary the sensitiveness of the.

brake application, by varying the force which urges or causes the piston 2 to return to its normal position. Such adjustment is .effected by an adjusting screw 6 extending axially through the head of the cylinder opposite the plunger 3. VThe inner end of the screw engages and is capable of axially adjusting a discv 6a against-which .the

outer end of the spring 4 is seated.'V Over the outer end of the screw 6 is a tight cap 6b which seals the cylinder againstl the admittance ofair by the adjusting screw 6. f

A-pairof brackets or arms 8 depend from the lower end of the casing` I and extend ,preferably to the front side. Onthe lower end'of these arms is mounted a rock shaft 9 onwhich is mounted and non-rotatably' secured a foot pedal I0 having a backwardly extending army Illa, the free end of which is pivotally connected,by a

ment 2| b is axially shiftably mounted a valve 22j which is urged', by a spring 23, against a seat 2 I c in the wall between the two compartments. The valve 22 is raised from its seat v by a fioating plunger'24 which is secured to the free inner portion of a cup shaped corrugated rubber boot or shield 25, and is axially located in the chamber 2lb; The outer open end of the shield is secured at the outer end of the cylindrical casing 2| bya cap 26. 'Ifo this cap is fastened one end ofthe flexible tube 2'Iaof a Bowden cable, the otherend ofwhich is secured to one of the arms 8 by a clip 28. In this tube is the cable 211? of the Bowden cable,v one end of which is secured to aA short arm IIIb extending from the pivotal axis of the pedal. The other end of the cable extends into the end of the plunger 24. In this manner, when the pedal is depressed, vthe cable 2lb raises theLplunger 24, unseats the valve 22,'` and connects the interior of the cylinder I with the source of vacuum through the pipe I2.

In order to applyy the brakes, the foot pedal I6 is depressed, unseating the valve 22, `connecting the vacuum to the interior of the cylinder I. The depressing of the foot pedal raises the plunger. (See Fig. 4.) Immediately the port 3d is closed, shutting off atmospheric pressure from .Y the brakes. As the-plunger is raised slightly further, the small portion of the port 3c connects with the movement of or application of the brakes. As

^ the plunger is raised further, the foregoing action upper end of its stroke.

is repeated until the plunger is forced to the (See Fig. 5.) The upward movement of the piston is limited by a shoulder Id at the upper end of the casing I. Thus it is seen that the port 3C, and all portions thereof, are continuously or repeatedly closed by the piston 2 when the plunger is raised. Therefore, the full fluid or vacuum pressure may be applied to the brakes when the plunger is fully raised. The relative positions of the plunger and piston are shown in Fig. 4.v The dotted line position of the piston shows the extreme upper position thereof when the plunger is shifted to the position shown. Rapid upward shifting of the plunger will be proportionably equalized by upward drawing of the piston. If the plunger is instantly forced its full distance upwardly full vacuum pressure is applied to'the brakes. The rapidity of the brake action or application is controlled by the sizes and number of ports for com- `munication of the vacuum or other fluid pressure, and by the tension of the spring 4 which is adjusted by the set screw 6.

When the pedal is released, the valve 22 is closed by the spring 23 and disconnects the source of vacuum from the cylinder I, and thereby reduces to a minimum the loss of the vacuum.

Though I have shown vand described a particular construction, combination and arrangement of parts and portions, vand certain applications thereof, and have referred particularlyto a vac- -'x uum control system, I do4 not wish to be limited to these, but desire to include in the scope of my invention the construction, combination and arrangement substantially as set forth in the appended claims. A

I claim:

V1. In a brake system for vehicle wheels, a valve mechanism for controlling connections from a fluid pressure means to a wheel brake mechanism, Acomprising a casing, a` plunger reciprocally l mounted therein, a 'spring between the casing and the plunger for forcing the plunger toward one end of the casing, a lever for manually shifting the plunger against the action of the spring,

a piston mounted in the casing, and another spring urging the piston in the direction in which the plunger is urged by its spring, the depression of the plunger against its spring connecting the fluid pressure means with the brake mechy anism and proportionately vurging the piston to compress its spring and ,partially to reduce the connection made by the plunger.

2. In a brake system for vehicle wheels, a valve mechanism for controlling the connection from a fluid pressure means to a wheel brake mechregister with said connections to the casing, ai spring adapted to force the piston towards one end of the casing, a plunger movably mounted in the piston and intersecting said passage and also having a transverse passage for connecting the opposite ends of the piston passage, means for urging the plunger inthe same direction as the piston is urged by its spring, and manual means for shifting the plunger, the shifting of the plunger proportionately urging the piston to compress its spring and thereby partially to reduce the connection made by the transverse passage of the plunger.

3. In a brake control valve means for controlling fluid pressure connections between a fluid pressure source and a wheel brake, comprising a casing adapted to be connected to said fluid pressure source and to said wheel brake, a piston movably mounted in the casing and having a port registering with the uid pressure connection, a spring adapted to force the piston toward one end of the casing, a plunger movably mounted in the piston adapted normally to cover said port, means for normally urging the plunger in the same direction as the piston is urged by its spring, a manual means for shifting the plunger against the latter'means, to uncover said port, the shifting of the plunger causing fluid pressure to act upon the piston, proportionably urging the' piston to compress its spring and thereby partially to reduce the port opening.

4. In a brake control valve means for controlling fluid pressure connections between a uid pressure source and a wheel brake, comprising a casing having one end adapted to be connected to the brake and the side adapted to be connected to said fluid pressure source, and having a passage adapted to connect said connections, a piston movably mounted in the casing, and having a side passage registering at all times with the side connection of the casing and the axial portion adapted to benconnected with the end connection of the casing leading to the brakes, a spring adapted to force the piston towards said one end of the casing, a plunger movably mounted in the piston and intersecting said passage of the casing and having a port adapted to register with the piston passage, means for urging the plunger in the same direction as the piston is urged by its spring, and manual means for shifting the plunger against the action of the spring, the shifting ofA the plunger causing fluid pressure to act upon the piston, proportionably urging the piston to compress its spring and thereby partially to reduce the port opening of the plunger.

5. In a brake apparatus of the class described, valve means for controlling fluid pressure connections between a iiuid pressure source and a wheel brake, comprising a casing connected to said fluid pressure source and to said wheel brake, a plunger reciprocally mounted in the casing, a piston also reciprocally mounted in the casing, separate springs urging the plunger and the piston to .one end of the casing tending to close the connections between the fluid pressure source and the brakes, a lever for manually shifting the plunger against the action of its spring, the depression of the plunger against its spring connecting the connections between the fluid pressure source and the brakes and adapted proportionably to force the piston to compress its spring and partially to reduce the connection made by the plunger, and a normally closed :duid pressure shut-oil valve for normally sealing the fluid pressure. source from the casing, the shuts off valve being operatively connected to the lever and opened when the plunger ,is operated to connect the lluid pressure source with the brake.

6. In a brake control Valve means for controlling iluid pressure connections between a fluid pressure source and a wheel brake, comprising a casing adapted to be connected to said fluid pressure source and to said wheel brake, a piston movably mounted in the casing and having a port registering with the fluid pressure connection, a spring adapted to force the piston toward one end of the casing, a plunger movably mounted in the piston adapted normally to move over and cover said port, means for normally urging the plunger in the same direction as the piston is urged by its spring, a manual means for shifting the plunger against the latter means, the shifting of the plunger causing fluid pressure to act upon the piston, proportionably urging the piston to compress its spring and thereby partially to reduce the port opening, and a normally closed iiuid pressure shutoff valve fornormally sealing the fluid pressure source from the casing, the shut-off valve being operatively connected to the manual means and operated when said plunger is shifted.

7. In a brake control valve means for controlling fluid pressure connections between a fluid pressure source and a Wheel brake, comprising a casing adapted to be connected to said fluid pressure source and to said wheel brake, a piston movably mounted in the casing and having a port registering with the fluid pressure connection, a spring adapted to force the piston toward one end of the casing, a plunger movably mounted in the piston and provided with a passage, means for normally urging the plunger in the same direction as the piston is urged by its spring, a manual means for shifting the plunger against the latter means, the shifting of the plunger connectlng said port and passage and thereby connecting the fluid pressure source to said brakes, the shifting of the plunger causing fluid pressure to act upon the piston, proportionably urging the piston to compress its spring and thereby partially to reduce the passage opening of the plunger, and a normally closed fluid pressure shut-olf valve for normally sealing the fluid pressure source from the casing, the shut-off valve being operatively connected to the manual means and operated when said plunger .is shifted.

v8. In a brake control valve means for controlling iiuid pressure connections between a fluid pressure source and a wheel brake, comprising a casing having one end adapted to be connected to the brake and the side adapted to be connected to said fluid pressure source, and having a passage adapted to connect said connections, a piston movably mounted in the casing, and having a side passage registering at all times with the side connection of the casing and the axial portion adapted to be connected with the end connection of the casing leading to the brakes, a spring ,adapted to force the piston towards said one en d of the casing, a plunger movably mounted in the piston and intersecting said passage of the casing and having a port adapted to register with the piston passage, means for urging the plunger in the same direction as the piston is urged by its spring, manual means for shifting the plunger against the action of the spring, the shifting of the plunger causing fluid pressure to act upon the piston, proportionably urging the piston to compress its spring and thereby partially to reduce the port opening of the plunger,

and a normally closed fluid pressure shut-olf valve for normally sealing the uid pressure source from the casing, the shut-off valve being operatively connected to the manual means and operated when said plunger is shifted.

A9. In a brake system for vehicle wheels, a valve mechanism for controlling the connection fromV a fluid pressure means to a wheel brake mechanism, comprising a casing having its intermediate portion connected to said means and one end connected to said brake mechanism and hav,- ing a passage therebetween adapted to connect said connections, a piston movably mounted in the casing, and having a passage adapted to register with said connections to the casing, a spring adapted to force the piston towards one end of the casing, a plunger movably mounted in the piston and intersecting said passage and also having a transverse passage for connecting the opposite ends of the piston passage, the transverse passage being elongated With respect to the longitudinal axis of the plunger and reduced in cross-section toward the brake connection end of the casing, means for urging the plunger in the same direction as the piston is urged by its spring, and manual means for shifting the plunger, the shifting of the plunger proportionately urging the piston to compress its spring and thereby partially to reduce the connection made by the transverse passage of the plunger.

10. In a brake control valve means for controlling fluid pressure connections between a fluid pressure source and a wheel brake, comprising a casing adapted to be connected to said fluid pressure source and to said wheel brake, a piston movably mounted in the casing and having a port registering with the fluid pressure connection, a spring adapted to force the piston toward one end of the casing, a plunger movably mounted in the piston adapted normally to cover said port, means for normally urging the plunger in the same direction as the piston is urged by its spring, v

a manual means for shifting the plunger against the latter means, vsaid plunger being provided with a transverse port adapted to register with the first port when the plunger is shifted by the manual means, the shifting of the plunger causing fluid pressure to act upon the piston, proportionably urging the piston to compress its spring and thereby partially to reduce the port opening.

11. In a brake control valve means for controlling luid pressure connections between a fluid pressure source and a wheel brake, comprising a casing adapted to be connected to said fluid pressure source and to said wheel brake, a piston movably mounted in the casing and having a port registering with the fluid pressure connection, a spring adapted to force the piston toward one end of the casing, a plunger mcvably mounted in the piston adapted normally to move over and cover said port, means for normally urging the plunger in the same direction as the piston is urged by its spring, a manual means for shifting the plunger against the latter means, said plunger being also provided with a transverse port adapted to register with the first port when the plunger is shifted by the manual means, the transverse port being elongated with respect to the longitudinal axis of the plunger and reduced in cross-section toward the brake connection portion of the casing, the shifting of the plunger causing fluid pressure to act upon the piston, prospring and thereby partially to reduce thelport opening.

12.- In a brake control valve means for controlling fluid pressure connections between a iiuid pressure -source and a wheel brake, comprising a casing'having one end adapted to be connected to the brake and the side adapted to be connected to said fluid pressure source, and having a passage adapted to connect said connections, a piston movably mounted in the casing, and having a side passage registering at all times with the side connection of the casing and the axial portion adapted to be connected with the end connection of the casing leading to the brakes, a spring adapted to force the piston towards said one end of the casing, a plunger movably mounted in the piston and intersecting said passage of the casing and having a port adapted to register with the piston passage, the port being elongated with reportionably' urging the piston to compress its 75 spect to the longitudinal axis of the plunger and reduced in cross-section toward the brake connection portion of the casing, means for urging the plunger in the same direction as the piston is urged by its spring, and manual means for shifting the plunger against the action of the spring, the shifting of the plunger causing fluid pressure to act upon the piston, proportionably urging the piston to compress its spring and thereby partially to reduce the port opening of the plunger.

13. In a brake control valve means for controlling iiuid pressure connections between a fluid pressure source and a wheel brake, comprising a casing having one end adapted to be connected to the brake and the side adapted to be connected t0 said uid pressure source, and having a passage adapted to connect said connections, a piston movably mounted in the casing, said piston having piston portions at its ends, there being provided a passage between the casing and piston ,intermediate the piston portions, said passage registering at all times with the side connection of the casing, said piston having an axial bore adapted to be connected with the end connection of the casing leading to the brakes, said bore being connected by a radial port to the space between the piston portions, a spring adapted to force the piston towards said one end of the casing,a hollow plunger movably mounted in the bore of the piston and having a transverse bore connecting the interior with the exterior of the plunger and adapted to register with the radial port, means for urging the plunger in the same direction as the piston is urged by its spring, and manual means for shifting the plunger against the action of the spring, the shifting of the plunger causing fluid pressure to act upon the piston, proportionably urging the piston to compress its spring and thereby partially to reduce the port opening of the plunger.

14. In a brake control valve means for controlling iiuid pressure connections between a iiuid' of the casing leading to the brakes, said bore being connected by a radial port to the space between the piston portions, a spring adapted to force the piston towards said one end of the casing, a hollow plunger movably mounted in the bore of the piston and having a transverse bore connecting the interior With the exterior of the plunger and adapted to register with the radial port, the transverse port being elongated with respect to the longitudinal axis of the plunger and reduced in cross-section toward the brake con- 10 

